我有一个 RECIPE
表,它与 INGREDIENT
表具有 OneToMany 关系,因为一个食谱可以有很多成分。问题是,如果用户删除了一个成分(它通过前端将所有字段(ingredient_id
和 ingredient
)设置为 NULL),那么包含两个表关系的行 RECIPE_INGREDIENT
已删除,但 Ingredient
表中的行仍然存在。我们不能告诉 Hibernate 也删除那些行吗?
Oracle 表
create table recipe(id number primary key,
name varchar2(25) unique);
create table ingredient(ingredient_id number(4) primary key,
ingredient varchar2(40));
create table recipe_ingredient(recipe_id number(4),
ingredient_id number(4),
constraint recipe_fk foreign key(recipe_id)
references recipe(recipe_id),
constraint ingredient_fk foreign
key(ingredient_id) references
ingredient(ingredient_id));
成分和配方 POJO
@Entity
@Table(name = "ingredient", uniqueConstraints={
@UniqueConstraint(columnNames="INGREDIENT_ID")
})
public class Ingredient implements Serializable {
@Id
@Column(name = "INGREDIENT_ID", unique=true, nullable=false)
@SequenceGenerator(name="seq_ingredient", sequenceName="seq_ingredient")
@GeneratedValue(strategy=GenerationType.AUTO, generator="seq_ingredient")
private Integer ingredientId;
@Column(name = "INGREDIENT")
private String ingredient;
/*@ManyToOne(fetch=FetchType.EAGER)
@JoinColumn(name="RECIPE_ID")
private Recipe recipe;*/
//getter and setters
@Entity
@Table(name = "recipe")
public class Recipe implements Serializable {
@Id
@Column(name = "id")
private Integer id;
@Column(name = "name")
private String name;
@OneToMany(cascade = CascadeType.ALL, fetch = FetchType.EAGER, orphanRemoval = true)
@JoinTable(name = "recipe_ingredient", joinColumns = { @JoinColumn(name = "recipe_id") }, inverseJoinColumns = { @JoinColumn(name = "ingredient_id") })
private List<Ingredient> ingredients;
//getters and setter
}
DAO 代码
public class RecipeDaoImpl implements RecipeDao {
public void addRecipe(Recipe recipe) {
getSession().saveOrUpdate(recipe);
}
}
日志显示 INGREDIENT
表中的行仍然存在,而 Hibernate 只是从“RECIPE_INGREDIENT”表中删除行。
请看下面删除ingredient_id
和null
。在这两种情况下,它都将 ingredient.recipe_id
更新为 NULL。
Received following from frontend:
RecipeController - Recipe[recipeId=126,name=Sandwich,ingredients=[Ingredient[ingredientId=270,ingredient=Salt],[ingredientId=<null>,quantity=<null>]]]
Hibernate: update RECIPE set NAME=? where RECIPE_ID=?
Hibernate: update ingredient set INGREDIENT=? where INGREDIENT_ID=?
Hibernate: delete from recipe_ingredient where recipe_id=?
Hibernate: insert into recipe_ingredient (recipe_id, ingredient_id) values (?, ?)
所以数据库表有,
INDREDIENT
INGREDIENT_ID INGREDIENT
271 Salt
272 Sugar
RECIPE_INDGREDIENT
RECIPE_ID INDREDIENT_ID
126 271
最佳答案
我通过将 insertable = false, updatable = false
作为属性添加到 @JoinColumn
像这样:
@JoinColumn(name="RECIPE_ID", insertable = false, updatable = false)
关于java - Hibernate 不删除外键行(而是将其设置为 NULL),我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/27309075/